Used to drink a 12 pack a night. Did that for about 10 years. One day my dad ask me if I thought about it when I drank like that. "Do you think your an alcoholic?" I had been thinking about it. His question was the only one and he let it go. He basically told me with that, that he saw an alcoholic in front of him. I decided to quit for a while and have not had it since. That was 14 years ago. About 6 months after I quit, I figured out that I had something that had been bothering me since I was a teenager.
Over the last decade, I thought about some things. I realized that if I was asking myself if I was drinking too much, I probably was. If you are asking the question, then a part of you is trying to tell you something.
CrackerJax is right, it is the reason more than the habit that you need to look at.